This invention relates to the field of shielding radioactive materials and, more particularly, to an improved syringe shield which is partially disposable.
The subject matter of this invention relates to subject matter disclosed in the copending application Ser. No. 668,532 entitled "Syringe Shield," filed of even date herewith and assigned to the same assignee as the present application.
For various types of diagnostic testing it is necessary to inject radioactive materials into a patient. It is well recognized that technicians who handle these materials need protection against the perils of cumulative ionizing radiation exposure, so provision is commonly made for shielding the materials until such time as they are injected into the patient. Toward this end, various types of syringe shields have been developed. The typical prior art syringe shield includes a lead cylinder which fits over a syringe, the lead body having a window of leaded glass which allows the operator to see the scale on the syringe which is placed within the lead cylinder.
There are a number of disadvantages associated with commercially available syringe shield designs. Some units have a simple cylindrical casing which does not provide adequate shielding forwardly or rearwardly of the syringe length. A further problem is that there is not standardization of syringe sizes, and even syringes having the same volume often have different physical dimensions. For example, a 10 cc syringe may have various possible diameters depending on the particular manufacturer. Thus, special provision is generally necessary to fit a syringe shield to the different possible syringe sizes. For example, in one prior art design the syringe shield is provided with a "set screw" which adjustably protrudes into the syringe shield's bore and engages the syringe so that it cannot move around within the syringe shield. The use of this technique involves some inconvenience and can occasionally cause breakage of the syringe.
Disposable syringes are in widespread use and their advantages are well recognized. Similar advantages would accrue if a disposable shielded syringe existed. For example, a disposable shielded syringe would eliminate the need for medical personnel to locate an appropriately sized syringe shield and assemble the syringe shield over the syringe to be used. The need to decontaminate, clean and maintain permanent syringe shields would also be eliminated. However, to applicant's knowledge no disposable shielded syringe has become commercially available. One reason for this void is the cost of a shielded syringe which includes such expensive parts as a leaded glass window. A further item of expense relates to the need for making shielded syringes suitable for use under hospital or laboratory sanitary conditions. The presence of a heavy shielding body, typically lead, is problematic in that an unfinished lead exterior tends to become dirty and contaminated and is unsuitable for hospital conditions. Provisions for special finishing or plating generally involves expense. As a result of these factors, the prospect of disposing of a syringe shield or of an integrally shielded syringe has not been commercially feasible.
It is an object of this invention to provide a solution to the prior art problems as set forth.